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61.
It is shown that the chronology of flare star discoveries in the Pleiades cluster and the Orion association can be described satisfactorily by various distribution functions (gamma, binomial, decreasing exponential, and delta) for the mean frequencies of stellar flares. However, it has been found that this is due to the uncertainty in the observationally derived distribution function for the mean frequency of stellar flares. The most likely function is that derived by Ambartsumian, which has a physical basis.Translated fromAstrofizika, Vol. 38, No. 1, pp. 25–32, January–March, 1995. 相似文献
62.
63.
64.
U-Pb (SHRIMP-II) isotopic dating has been conducted for zircons of the ash sediments of the Ust’-Suifun Suite, which was the
final stage of Late Cenozoic explosive volcanism in Southwest Primorskii krai. These pyroclastic units are widespread within
sediments that fill in Cenozoic depressions including large coalfields. The concordant dates (23.7–24.6 Ma) are in line with
the results of the K-Ar determinations for volcanic tephra (23.6–27.1 Ma) and correspond to the beginning of the active phase
of spreading and taphrogenesis in the neighboring Trench of the Sea of Japan. These processes started as early as the Eocene
and are reflected in the continental vicinity with the formation of riftogenic depressions and the occurrence of a peculiar
gas volcanism. 相似文献
65.
Ostapchuk A. A. Kocharyan G. G. Morozova K. G. Pavlov D. V. Gridin G. A. 《Izvestiya Physics of the Solid Earth》2021,57(5):659-670
Izvestiya, Physics of the Solid Earth - Abstract—Granular media determine the dynamics of many natural systems including faults in the Earth’s crust. The paper addresses the laboratory... 相似文献
66.
This article gives an account of the results of the U-Pb-SHRIMP study of zircons derived from gneissoid and equigranular granitoids
of the Malka Uplift of the Sredynnyi Range in Kamchatka. It was established that intrusion and crystallization of granitoids
occurred in the time interval from 76.2 ± 1.5 to 83.1 ± 2.0 Ma. The texture of zircon crystals suggests their magmatic origin.
The obtained data reliably confirm that granite formation and emplacement of the recently formed continental crust in Kamchatka
took place in the Late Cretaceous (Campanian). 相似文献
67.
Mohammed Abdul Rasheed M. Lakshmi P. L. S. Rao D. J. Patil A. M. Dayal V. Sudarshan 《Natural Resources Research》2012,21(4):427-441
Mesozoic sediments are source rocks for nearly half the world’s hydrocarbon reserves. Hence, there is great interest in the oil industry to know the trap and sub-trappean sediment thickness and their extent in the trap covered regions of Jamnagar study area. The microbial prospecting method is applied in the Jamnagar sub-basin, Gujarat for evaluating the prospects for hydrocarbon exploration by investigating the anomalous abundance of n-pentane- and n-hexane-oxidizing bacteria of this area. A total of 150 near-surface soil samples were collected in Jamnagar sub-basin, Gujarat for the evaluation of hydrocarbon resource potential of the basin. In this study, bacterial counts for n-pentane-utilizing bacteria range between 1.09 × 102 and 9.89 × 105 cfu/g and n-hexane-utilizing bacteria range between 1.09 × 102 and 9.29 × 105 cfu/g. The adsorbed hydrocarbon gases consisting of ethane plus hydrocarbons (ΣC2+) of 1–977 ppb and n-pentane (nC5) of 1–23 ppb. The integrated geomicrobial and adsorbed soil gas studies showed the anomalous hydrocarbon zones nearby Khandera, Haripur, and Laloi areas which could probably aid to assess the true potential of the basin. Integrated geophysical studies have shown that Jamnagar sub-basin of Saurashtra has significant sediment thickness below the Deccan Traps and can be considered for future hydrocarbon exploration. 相似文献
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69.
This paper traces the theoretical development of the regional concept and the use of regionalization techniques in Soviet geography and seeks to compare this history with comparable trends in Western geography. It is severely critical of the major and rapid paradigm shifts noticed in post-war Western geographical science and relates these to shifts in the approach to global development issues. 相似文献
70.
M. V. Martynova 《Water Resources》2012,39(2):223-228
The causes of the high Mn concentration in the solid phase and pore solution of bottom sediments in the Mozhaisk Reservoir
are discussed. Regularities are identified in variations the concentrations of Mn forms in reservoir deposits from its upper
part to the dam. 相似文献